7.93 The following figure appeared in the paper “EDTAExtractable Copper, Zinc, and Manganese in Soils of the Canterbury Plains” (New Zealand Journal of Agricultural Research [1984]: 207–217). A large number of topsoil samples were analyzed for manganese (Mn), zinc

(Zn), and copper (Cu), and the resulting data were summarized using histograms.

The investigators transformed each data set using logarithms in an effort to obtain more nearly symmetric distributions of values. Do you think the transformations were successful? Explain.